kernel-fxtec-pro1x/include/linux/sunrpc/clnt.h
Trond Myklebust 006abe887c SUNRPC: Fix a race in rpc_info_open
There is a race between rpc_info_open and rpc_release_client()
in that nothing stops a process from opening the file after
the clnt->cl_kref goes to zero.

Fix this by using atomic_inc_unless_zero()...

Reported-by: J. Bruce Fields <bfields@redhat.com>
Signed-off-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Cc: stable@kernel.org
2010-09-12 19:55:25 -04:00

307 lines
9.1 KiB
C

/*
* linux/include/linux/sunrpc/clnt.h
*
* Declarations for the high-level RPC client interface
*
* Copyright (C) 1995, 1996, Olaf Kirch <okir@monad.swb.de>
*/
#ifndef _LINUX_SUNRPC_CLNT_H
#define _LINUX_SUNRPC_CLNT_H
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/sunrpc/msg_prot.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/xprt.h>
#include <linux/sunrpc/auth.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/timer.h>
#include <asm/signal.h>
#include <linux/path.h>
#include <net/ipv6.h>
struct rpc_inode;
/*
* The high-level client handle
*/
struct rpc_clnt {
atomic_t cl_count; /* Number of references */
struct list_head cl_clients; /* Global list of clients */
struct list_head cl_tasks; /* List of tasks */
spinlock_t cl_lock; /* spinlock */
struct rpc_xprt * cl_xprt; /* transport */
struct rpc_procinfo * cl_procinfo; /* procedure info */
u32 cl_prog, /* RPC program number */
cl_vers, /* RPC version number */
cl_maxproc; /* max procedure number */
char * cl_server; /* server machine name */
char * cl_protname; /* protocol name */
struct rpc_auth * cl_auth; /* authenticator */
struct rpc_stat * cl_stats; /* per-program statistics */
struct rpc_iostats * cl_metrics; /* per-client statistics */
unsigned int cl_softrtry : 1,/* soft timeouts */
cl_discrtry : 1,/* disconnect before retry */
cl_autobind : 1,/* use getport() */
cl_chatty : 1;/* be verbose */
struct rpc_rtt * cl_rtt; /* RTO estimator data */
const struct rpc_timeout *cl_timeout; /* Timeout strategy */
int cl_nodelen; /* nodename length */
char cl_nodename[UNX_MAXNODENAME];
struct path cl_path;
struct rpc_clnt * cl_parent; /* Points to parent of clones */
struct rpc_rtt cl_rtt_default;
struct rpc_timeout cl_timeout_default;
struct rpc_program * cl_program;
char cl_inline_name[32];
char *cl_principal; /* target to authenticate to */
};
/*
* General RPC program info
*/
#define RPC_MAXVERSION 4
struct rpc_program {
char * name; /* protocol name */
u32 number; /* program number */
unsigned int nrvers; /* number of versions */
struct rpc_version ** version; /* version array */
struct rpc_stat * stats; /* statistics */
char * pipe_dir_name; /* path to rpc_pipefs dir */
};
struct rpc_version {
u32 number; /* version number */
unsigned int nrprocs; /* number of procs */
struct rpc_procinfo * procs; /* procedure array */
};
/*
* Procedure information
*/
struct rpc_procinfo {
u32 p_proc; /* RPC procedure number */
kxdrproc_t p_encode; /* XDR encode function */
kxdrproc_t p_decode; /* XDR decode function */
unsigned int p_arglen; /* argument hdr length (u32) */
unsigned int p_replen; /* reply hdr length (u32) */
unsigned int p_count; /* call count */
unsigned int p_timer; /* Which RTT timer to use */
u32 p_statidx; /* Which procedure to account */
char * p_name; /* name of procedure */
};
#ifdef __KERNEL__
struct rpc_create_args {
int protocol;
struct sockaddr *address;
size_t addrsize;
struct sockaddr *saddress;
const struct rpc_timeout *timeout;
char *servername;
struct rpc_program *program;
u32 prognumber; /* overrides program->number */
u32 version;
rpc_authflavor_t authflavor;
unsigned long flags;
char *client_name;
struct svc_xprt *bc_xprt; /* NFSv4.1 backchannel */
};
/* Values for "flags" field */
#define RPC_CLNT_CREATE_HARDRTRY (1UL << 0)
#define RPC_CLNT_CREATE_AUTOBIND (1UL << 2)
#define RPC_CLNT_CREATE_NONPRIVPORT (1UL << 3)
#define RPC_CLNT_CREATE_NOPING (1UL << 4)
#define RPC_CLNT_CREATE_DISCRTRY (1UL << 5)
#define RPC_CLNT_CREATE_QUIET (1UL << 6)
struct rpc_clnt *rpc_create(struct rpc_create_args *args);
struct rpc_clnt *rpc_bind_new_program(struct rpc_clnt *,
struct rpc_program *, u32);
struct rpc_clnt *rpc_clone_client(struct rpc_clnt *);
void rpc_shutdown_client(struct rpc_clnt *);
void rpc_release_client(struct rpc_clnt *);
void rpc_task_release_client(struct rpc_task *);
int rpcb_register(u32, u32, int, unsigned short);
int rpcb_v4_register(const u32 program, const u32 version,
const struct sockaddr *address,
const char *netid);
int rpcb_getport_sync(struct sockaddr_in *, u32, u32, int);
void rpcb_getport_async(struct rpc_task *);
void rpc_call_start(struct rpc_task *);
int rpc_call_async(struct rpc_clnt *clnt,
const struct rpc_message *msg, int flags,
const struct rpc_call_ops *tk_ops,
void *calldata);
int rpc_call_sync(struct rpc_clnt *clnt,
const struct rpc_message *msg, int flags);
struct rpc_task *rpc_call_null(struct rpc_clnt *clnt, struct rpc_cred *cred,
int flags);
int rpc_restart_call_prepare(struct rpc_task *);
int rpc_restart_call(struct rpc_task *);
void rpc_setbufsize(struct rpc_clnt *, unsigned int, unsigned int);
size_t rpc_max_payload(struct rpc_clnt *);
void rpc_force_rebind(struct rpc_clnt *);
size_t rpc_peeraddr(struct rpc_clnt *, struct sockaddr *, size_t);
const char *rpc_peeraddr2str(struct rpc_clnt *, enum rpc_display_format_t);
size_t rpc_ntop(const struct sockaddr *, char *, const size_t);
size_t rpc_pton(const char *, const size_t,
struct sockaddr *, const size_t);
char * rpc_sockaddr2uaddr(const struct sockaddr *);
size_t rpc_uaddr2sockaddr(const char *, const size_t,
struct sockaddr *, const size_t);
static inline unsigned short rpc_get_port(const struct sockaddr *sap)
{
switch (sap->sa_family) {
case AF_INET:
return ntohs(((struct sockaddr_in *)sap)->sin_port);
case AF_INET6:
return ntohs(((struct sockaddr_in6 *)sap)->sin6_port);
}
return 0;
}
static inline void rpc_set_port(struct sockaddr *sap,
const unsigned short port)
{
switch (sap->sa_family) {
case AF_INET:
((struct sockaddr_in *)sap)->sin_port = htons(port);
break;
case AF_INET6:
((struct sockaddr_in6 *)sap)->sin6_port = htons(port);
break;
}
}
#define IPV6_SCOPE_DELIMITER '%'
#define IPV6_SCOPE_ID_LEN sizeof("%nnnnnnnnnn")
static inline bool __rpc_cmp_addr4(const struct sockaddr *sap1,
const struct sockaddr *sap2)
{
const struct sockaddr_in *sin1 = (const struct sockaddr_in *)sap1;
const struct sockaddr_in *sin2 = (const struct sockaddr_in *)sap2;
return sin1->sin_addr.s_addr == sin2->sin_addr.s_addr;
}
static inline bool __rpc_copy_addr4(struct sockaddr *dst,
const struct sockaddr *src)
{
const struct sockaddr_in *ssin = (struct sockaddr_in *) src;
struct sockaddr_in *dsin = (struct sockaddr_in *) dst;
dsin->sin_family = ssin->sin_family;
dsin->sin_addr.s_addr = ssin->sin_addr.s_addr;
return true;
}
#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
static inline bool __rpc_cmp_addr6(const struct sockaddr *sap1,
const struct sockaddr *sap2)
{
const struct sockaddr_in6 *sin1 = (const struct sockaddr_in6 *)sap1;
const struct sockaddr_in6 *sin2 = (const struct sockaddr_in6 *)sap2;
return ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr);
}
static inline bool __rpc_copy_addr6(struct sockaddr *dst,
const struct sockaddr *src)
{
const struct sockaddr_in6 *ssin6 = (const struct sockaddr_in6 *) src;
struct sockaddr_in6 *dsin6 = (struct sockaddr_in6 *) dst;
dsin6->sin6_family = ssin6->sin6_family;
ipv6_addr_copy(&dsin6->sin6_addr, &ssin6->sin6_addr);
return true;
}
#else /* !(CONFIG_IPV6 || CONFIG_IPV6_MODULE) */
static inline bool __rpc_cmp_addr6(const struct sockaddr *sap1,
const struct sockaddr *sap2)
{
return false;
}
static inline bool __rpc_copy_addr6(struct sockaddr *dst,
const struct sockaddr *src)
{
return false;
}
#endif /* !(CONFIG_IPV6 || CONFIG_IPV6_MODULE) */
/**
* rpc_cmp_addr - compare the address portion of two sockaddrs.
* @sap1: first sockaddr
* @sap2: second sockaddr
*
* Just compares the family and address portion. Ignores port, scope, etc.
* Returns true if the addrs are equal, false if they aren't.
*/
static inline bool rpc_cmp_addr(const struct sockaddr *sap1,
const struct sockaddr *sap2)
{
if (sap1->sa_family == sap2->sa_family) {
switch (sap1->sa_family) {
case AF_INET:
return __rpc_cmp_addr4(sap1, sap2);
case AF_INET6:
return __rpc_cmp_addr6(sap1, sap2);
}
}
return false;
}
/**
* rpc_copy_addr - copy the address portion of one sockaddr to another
* @dst: destination sockaddr
* @src: source sockaddr
*
* Just copies the address portion and family. Ignores port, scope, etc.
* Caller is responsible for making certain that dst is large enough to hold
* the address in src. Returns true if address family is supported. Returns
* false otherwise.
*/
static inline bool rpc_copy_addr(struct sockaddr *dst,
const struct sockaddr *src)
{
switch (src->sa_family) {
case AF_INET:
return __rpc_copy_addr4(dst, src);
case AF_INET6:
return __rpc_copy_addr6(dst, src);
}
return false;
}
/**
* rpc_get_scope_id - return scopeid for a given sockaddr
* @sa: sockaddr to get scopeid from
*
* Returns the value of the sin6_scope_id for AF_INET6 addrs, or 0 if
* not an AF_INET6 address.
*/
static inline u32 rpc_get_scope_id(const struct sockaddr *sa)
{
if (sa->sa_family != AF_INET6)
return 0;
return ((struct sockaddr_in6 *) sa)->sin6_scope_id;
}
#endif /* __KERNEL__ */
#endif /* _LINUX_SUNRPC_CLNT_H */